The invention relates to a procedure for determining at least one misfiring cylinder of a combustion engine.
It is known from prior use to determine misfiring cylinders of a combustion engine by measuring the time for the passage of an angle segment and by creating uneven running values from those time measurements. The uneven running values can for example be stated as angle accelerations or values that are equivalent or derived from it. Usually a positive uneven running corresponds with a misfiring cylinder and a negative uneven running with a firing cylinder.
The determination of a misfiring cylinder is important in order to comply with statutory provisions for an onboard diagnosis, in order to avoid catalytic converter damages and in order to be able to switch off the misfiring cylinder or cylinders of the combustion engine, so that the combustion engine can be further operated on the remaining cylinders. The switching off of a wrong cylinder, thus of a not misfiring cylinder, can cause that the combustion engine cannot be operated anymore.
It has shown that a reliable determination of at least one misfiring cylinder of a combustion engine is not ensured under all operating conditions of a combustion engine.